Rotary pump



May 39 P. R. FINCH ROTARY PUMP Original Filed Dec. 27, 1923` I l PAULRQFJJYUH Patented May 3, 1927.

UNITED STATES PATENT OFFICE.

, PAUL n. FINOH, or nEs MOINES, IOWA, AssIGNoR 'ro ALVAII O. WHITE, or nEs MOINES, IOWA.

ROTARY PUMP.

Original application iiled December 27, 1923, Serial No. 682,873, and in Canada August 22, 1925.

and `this application led July 17, 1926.

` The subject matter of this invention was originally included in but has been divided from my application filed December 27, 1923, Serial Number 682,873. v

` The object of the present invention is to provide an improved construction for a rotary compressor or pump. y

` lA further Object is to provide an improved rotary compressor or pump having a compressor chamber divided into two compartments by means including a hinged plate having slidable connections with an impeller and engaging a wall of the chamber.

\ l A further Objectis to provide an improved construction for a compressor having a rotary or oscillating impeller and having efficient means, so arranged as tor-prevent leakage, for bridging the space between the 1mpeller and the wall of a chamber whereby said chamber is divided into two separate compartments.

With these and other objects in view,L my invention consists in the construction, arrangement and combination of elements hereinafter set forth, pointed out in the claims and illustrated by the accompanying drawing, in which- Figure 1 .is a side elevation, partly in section, showing a double or two-stage compressor embodying my invention.

Figure 2 is a cross-section on the line 2-2 of Figure 1.

Figure 3 is a detailv section on the line 3?, of Figure v2.

In the construction of the device as shown in Figures 1, 2 and 3 the numeral 10 designatesgenerally a casing having end plates 11, 12 secured to its Walls by means of bolts 18. The casing 10 is formed with a substantially cylindrical chamber 14 and a chamber 15 communicating therewith by means of a V.passage 16 extending from end to endof said chambers. The chamber 15 has one wall Y formed on an irregular curve or on an arc of .a circle of considerably greater diameter than that of the chamber 14 and merging into the wall of the latter, the partition 17 between said chambers being formed on curves and terminatingshort lof the larger arc ofthe, chamber 15 to produce the passage 16. As shown,-the chamber 14 isA at the top of the casing and the chamber 15 at its base, but the position may be reversed or the com- Divided Serial No. 123,181.

pressor placed in any suitable position vfor operation.`

The compressor may be formed with double casings of like character and arrange ment as is specifically illustrated in Figure 1, to produce a double stage compressor, but l do not wish to be understood as limiting myself to this construction, and will lirst proceed to describe my invention as if it embodied the single stage compressor.

A shaft 18 ismounted longitudinally and axially of the chamber 14, is'journaled for rotation in bearings .19 and`20 in the end plates 11 and 12, projects therefrom and is provided with one or more belt or fly wheels `such as421v at its ends. In the single stage type there are preferably two of the fly wheels 21, one at each end of the shaft, in order to properly balance the moving parts.

An impeller is provided and it has asubstantially cylindrical portion 22 ofV less diameter than the chamber 14 and mounted therein, and is formed with a central longi-A tudinal bore 23 through which the shaft 18 extends loosely. Formed on or fixed to the shaft 18 are one or more eccentrics 24 fitting the .bore of the impeller 22, and said eccentrics serve to hold the impeller eccentrically of the chamber 14 and to give it a circular orbital movement therein, in contact with ythe chamber walls, when the shaft is rotated.

one margin formed on a curve or arc con- .forming somewhat to that of the inner Wall of the chamber 15 and where it merges or blends into the Wall of the chamber However, either the Outer. surface Vof the blade 25, or the adjacent wall of the chamber 15, must be formed on a slightly irregular curve in order that the moving contact `may be maintained at all times as the impeller is oscillated. The impeller blade 25, it

will be understood, projects through the pas-'f' sage 16 and its major portion is within the chamber 1.5. y

The impeller` blade 25 terminates in a flange 26 arranged inra position substantially radially of the chamber 15. A rocking partition member 27, formed with trunnions 28, is journaled in the terminal portion of the chamber 15 and is engaged slidably by clamping plates 29 and 30 arranged on opposite sides thereot` and spaced apart at their upper margins by spacing blocks 31, and secured to the l'lange 26 by means ot bolts or screws extending through said blocks. Other bolts or screws 33 may be provided extending through the plates 29 and 30 and into the flange 26 and passing loosely through slots 34.; in the movable partition 2T to permit sliding movement el" said clamping plates and said bolts or screws relative to said partition plate.

Connnimication ports 35 and 36 are provided tor the chamber 15, opening thereto trom opposite sides o1 the partition termed therein by the impeller blade 25, the plates 29 and 3() and the partition plate 2T, which partition plate has a rocking contact with the wall of the said chamber' 15.

1n practical use the compr-essor may be driven by any desired means and as the shaft 18 is rotated the cams or eecentrics 2d thereon cause the impeller to revolve in its orbit, having a moving contact at changing points ot its periphery with the periphery of the chambers 14 and 15, and such rotation may be in either direction. Assuming that the shalt 18 is rotated countercloclnvise, the point of close Contact of the impeller with the casing also moves counterelockvvise, and the curved blade 25 is lowered at the point a into close contact with the inner Wall of the chamber 15 at the point o, in Which position the point c of the impeller head 22 is also in close contact with the Wall ot the chamber 14 at point d, and the intake port 3G is closed. rlhe charge drawn into the casing by this movement will be trapped Within the chamber 1.5 because ot the close Contact at two points as above referred to. As the countcrcloclnvise oscillation continues, the two points of contact move in the same direction until the blade 25 contacts at point c with the wall oit chamber 15 at point 7 and the impeller contacts at point g with wall ot chamber l/l-at point 7i. or adjacent the opening 1G. lt will be observed that the size of the trapped portion between the points fix-b and c-d is greater than that ot the last described portion between the points e-' and gw/i owing to the difference of radii ot the curves of casing 10, impeller 22 and blade 25, so that the volume ot the charge Vis reduced during` such movement. A further counter-clockwise inovement of the impeller will then act to discharge. the t'apped charge directly through the passage 16 and the exhaust port 35, It will also be observed that in such counter-clockwise movement, a portion ot the chamber 15 between the point of contact oit blade 25 and Wall of the chamber and the intake port 36 Will be enlarged, thus acting to draw in a new charge. The movement is continued until the parts are in the position shown in Figure 2, which constitutes a. complete cycle, and it will be seen that at all times some point ot impeller or blade 25 will have close contact with some point olf the wall ot casing 1t), and a part ot the time there is double contact; and at no time will there, be an open passage between the ports 235 and rlfhus a high pressure, or vacuum, is at no time permitted to liash irom one ot said ports to the other. This insures minimum loss ot volume and more silent operation.

lt is to be understood that the device may also be operated in a clockwise direction, the dii'lerence being that the volume ot the trapped charge will tend to be increased throughout certain arcs ot movement instead ot' reduced; and througliout other arcs ot movement the charge will be discharged directly through the port 36.

The passage 1G is out sufficient width to permit the described oscillation ot the impeller blade 25 without contact with the partition 1T, and the movement of the blade causes a corresponding movement of the clamping plates 29 and 30, Which slide on the partition plate 27, causing it to rock on its trunnions 28, at all times maintaining a contact at its lower margin, which preterably is rounded, with the adjacent wall oi the chamber 15. rlhe clamping plates and partition plate also extend trom end to end of the chamber and have a Working contact with the end Walls of the housing such that comparatively little leakage of fluid can occur.

lVhen it is desired to employ this construed tion in a tweetage ctnni'n'essor as specilically shown in VFigure 1, two similar housings Il) and lll are employed which are arranged in like position. rl`he housings l() and lll are separated in this instance by a relatively heavy partition or common intermediate wall 37, having bearings such as 38 tor the trunnioiis 28 o1'l the partition plates 2T and also having bearings (not shown) tor the inner ends ot the shafts 18. The two casings 10 and 1U are formed with similar chambers, impellers, impeller blades and parlit-ion plates as previtnislyv described, and these members are arranged in like relation in the two casings. rl`he exhaust port of the .first chamber 1t) is closed as by means ot a plug 39, and the intake port 36 ol the second cas ing is similarly closed by means o'll a plug 40, so that the two may be caused to operate together. Communication is provided between the two casings by means ot' a passage Ll1 formed longitudinally in the central plate 37 and having a port 42 extending laterally to the exhaust portion of the casing` 10 and a port 43 extending laterally to the intake portion of the chamber 10. By this means lofi lll)

Alt)

the compressed charge from the casing or lirst stage compressor is passed on to the casing 10 or second stage compressor and there further compressed and discharged through the outlet port of said casing. The second stage compressor is of less capacity than the first, which may be accomplished by making the casing 10 of less length than the lirst casing 10, as shown in Figure 1, or by increasing the size ot the impeller in the second casing, or both. In either event the impeller of the second stage compressor has less centrifugal force in operation than that of the first and as they have their eccentrics oppositely arranged, said second impeller only partially counterbalances the first impeller; the differenence in counterbalancing being accomplished by a fly wheel 21 at one end of the device, and it is possible to omit the 'ly wheel at the other end, which would have to be employed in the case ot' a single stage compressor.

The device is provided with suitable gaskets such as 44 between the several casings and partitions or end plates, and said casings are also provided with circumferential ribs or flanges 45 which serve to strengthen and reentorce them and also provide seats for the connecting bolts 13. Y

In connect-ion with the showing in Figure 2, it will be understood that when the device is used as a single stage compressor, vthe ports 42 and 43 will notV occur but end plates like 11 and l2 will be used at the ends of the single casing 10.

I claim as my invention l. A compressor' comprising a substantially cylindrical chamber, a second chamber communicating with the first and having intake and exhaust ports, an eccentrically movable,

substantially cylindrical impeller within the cylindrical chamber having traveling contact with the wall of the latter, a curved blade projecting from the impeller and extending into the second chamber, a partition plate mount-ed for rocking movement in the second chamber and having one margin roundcd and in contact with a wall of said chamber between the intake and exhaust ports, and slidable connections between said partition plate and the free end of said curved blade.

irregular curve and the other on an arc of Y a circle.

3. A compressor' comprising a casing, an impeller mounted for oscillatory movement therein, partitioning means between said impeller and casing wall, the inner wall of the casing and the periphery of the impeller each being 'formed on a plurality of curves of different radii whereby there is always one or more points of close moving contact ofsaid periphery withfsaid wall.

4. A compressor comprising'a casing, an

impeller mounted for oscillatory movement.

therein, partitioning means between one p0rtion of said impeller and the wall of the casing, the inner wall ofthe casing bein y formed on a plurality of curves, and a cran or cam shaft mounted for rotation concentrically of one portion of said inner wall and eccentrically of another portion thereof, said impeller being formed with a bearing, 'for said shaft which is located ooncentrically with respect to one portion of the periphery ot said impeller, another portion of said periphery being formed on an irregular curve. y

5. A double stage compressor comprising two casings, a shaft extending through and journaled in both of said casings, an impeller' mounted for oscillation on said sha-ft in each of said casings and in opposition to each other, one of said casings being oit greater capacity than the other and the impeller therein consequently having less centrifugal force in operation than that in the casing ot' greater capacity, whereby the lesser impeller partially coiunterbalances the other impeller, and a Hy wheel on said shaft outside the casings completing the counterbalancing of the greater impeller.

PAUL R. FINCH. 

